Installed a 8.5 BL and +8mm Chassis
- soniccj5
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Installed a 8.5 BL and +8mm Chassis
The fastest motor I have run in my RC-10/RC-10B4/SC10 has been a 10.5. Sure that is plenty for an indoor track, but I am always struggling to make the triples or quads. If I was not setup and already gaining speed before the jump, I would come up short. Most everyone else at the track has either 7.5 or 8.5 and made the jumps look easy.
Last night I removed my 10.5 stator and installed an 8.5. After a short trip down my street I can already tell this will make for some interesting laps.
And don't worry, only the B4 and SC10 will see this motor.
Last night I removed my 10.5 stator and installed an 8.5. After a short trip down my street I can already tell this will make for some interesting laps.
And don't worry, only the B4 and SC10 will see this motor.
- RC10th
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Re: Installed a 8.5 BL
Is the track big enough to run boost timing or do you guys run under a blinky rule?
I was old school - when old school wasn't cool !
- soniccj5
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Re: Installed a 8.5 BL
In 17.5 it is under blinky law, but mod buggy is open. Track is a good size.
Size: 100’ x 50’
Drivers Stand: 40′ long with a base height of 8′
Surface: Hard Packed Clay with Medium/High Bite with low pin indoor tires

http://www.rcexcitement.com/
Size: 100’ x 50’
Drivers Stand: 40′ long with a base height of 8′
Surface: Hard Packed Clay with Medium/High Bite with low pin indoor tires

http://www.rcexcitement.com/
- RC10th
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Re: Installed a 8.5 BL
Personally I think the 8.5 is a great motor, awesome drivability. Put a bit of timing in it and it has to potential to be an animal and everything between. The 8.5 can take quite a bit and it's happy doing it.
Super smooth, long run times and the top speed of a 4.5 !!
Good choice
Super smooth, long run times and the top speed of a 4.5 !!
Good choice

I was old school - when old school wasn't cool !
- DerbyDan
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Re: Installed a 8.5 BL
That track looks great! I wish we had some tracks like that over here, I've never raced on a full-on dirt track before
On the subject of brushless motors I think there's a lot of hype over just how powerfull they are/can be - for sure a 4.5 is frankly bonkers, but something like a 7.5 is very similar to a decent 12 turn brushed motor (the brushed motor just lacks that initial grunt from low-down) - I'm currently running a 7.5 in my modern 2wd but I've ran a 'softer' 6.5 in my Stealth RC10 racer & my Losi XX & I've recently run an 8.5 in my Jrx2 - all of which have proved perfectly controllable on the relatively high grip tracks we have here in the UK, without ripping apart the respective gearboxes, but most importantly have supplied enough power to negotiate the larger/multiple ramps & jumps that we now seem to have on our tracks these days!

On the subject of brushless motors I think there's a lot of hype over just how powerfull they are/can be - for sure a 4.5 is frankly bonkers, but something like a 7.5 is very similar to a decent 12 turn brushed motor (the brushed motor just lacks that initial grunt from low-down) - I'm currently running a 7.5 in my modern 2wd but I've ran a 'softer' 6.5 in my Stealth RC10 racer & my Losi XX & I've recently run an 8.5 in my Jrx2 - all of which have proved perfectly controllable on the relatively high grip tracks we have here in the UK, without ripping apart the respective gearboxes, but most importantly have supplied enough power to negotiate the larger/multiple ramps & jumps that we now seem to have on our tracks these days!
My T.C Showroom; http://www.tamiyaclub.com/member.asp?id=28990
- soniccj5
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Re: Installed a 8.5 BL
Video from the last big event at my local track. I think I was at home sleep during this race though. It was a long weekend!!
[youtube]Z6953FFrIfw[/youtube]
[youtube]Z6953FFrIfw[/youtube]
- flipwils11
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Re: Installed a 8.5 BL
This is good info to read through. I have a 10.5T speed passion and I finally hooked up the RS pro to the Tekin Hotwire for some timing and turbo settings today. I am still experimenting but so far so good. I think it is running as fast or nearly as fast as my 8.5T speed passion does.
Btw really enjoyed the video of that track, looks like a lot of fun.
Btw really enjoyed the video of that track, looks like a lot of fun.
- soniccj5
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Re: Installed a 8.5 BL
Got a chance to run the 8.5 this past weekend. 20/81 seemed to work well for the track with a little slip dialed in to prevent wheelies.
Now I have a +8mm chassis on order
Now I have a +8mm chassis on order

- Charlie don't surf
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Re: Installed a 8.5 BL
Sometimes it's a matter of throttle application or not before the jump face and where your throttle is on the jump face, if your rebounding on the face, you'll short it-soniccj5 wrote:The fastest motor I have run in my RC-10/RC-10B4/SC10 has been a 10.5. Sure that is plenty for an indoor track, but I am always struggling to make the triples or quads..
But when you can do it successfully with a 10.5 then your driving well, and fluidsoniccj5 wrote: If I was not setup and already gaining speed before the jump, I would come up short. .

A good 10.5 geared, timed and boosted properly will run any 8.5 down on a track like that, fewer wheelies and overpowering.soniccj5 wrote: Most everyone else at the track has either 7.5 or 8.5 and made the jumps look easy. .
Not busting on you at all, just mentioning that several factors can be in play, and slightly less power can benefit you as a driver from time to time

- RC10th
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Re: Installed a 8.5 BL
We all went away from the low turn motors in mod offroad and run anything from 8.5 to nothing lower than 6.5. Boost and timed they are much smoother to drive and just as fast.
Even the 10.5 onroad guys were only about a second slower than the mod guys running 3.5's
The secret I believe is to run no turbo delay as this makes the throttle feel linear, you wouldn't even know it had any turbo timing by driving it. Plus, nothing is worse then a delay and turbo kicking in as you leave a jump. I also had to run stock spec software with my 8.5 to get enough timing, most mod software doesn't have aggresive enough boost timing.
Even the 10.5 onroad guys were only about a second slower than the mod guys running 3.5's
The secret I believe is to run no turbo delay as this makes the throttle feel linear, you wouldn't even know it had any turbo timing by driving it. Plus, nothing is worse then a delay and turbo kicking in as you leave a jump. I also had to run stock spec software with my 8.5 to get enough timing, most mod software doesn't have aggresive enough boost timing.
I was old school - when old school wasn't cool !
- soniccj5
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Re: Installed a 8.5 BL
Something else I learned this weekend was how ride height makes a difference when hitting the jumps. I was still having issues hitting the triple, then I increased my ride height and I had liftoff.
Guess I'm over compensating for my horrible driving
Guess I'm over compensating for my horrible driving

- Orange
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- soniccj5
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Re: Installed a 8.5 BL
Would that cause cornering issues? Trying to get a better handle on handling setups.Orange wrote:Stiffer springs in the rear will help too.
- Orange
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Re: Installed a 8.5 BL
I have never seen you drive, so hard for me to know if it would help or not help... But it sounds like you need a little lift off the jump... If you are close and you think you can get away with going up to the next stiffer spring, then its an easy thing to try. Not like you have to rebuild the shock to do it.... One screw, change spring and re-set ride height... Changing the ride height will affect cornering too though. 
I guess if it were me and I felt like I could afford to lose a touch of traction in the corners, I would try the next spring up... if I have too much rotation in the corners and I can't change the spring because of it... I may have more issues than just getting over the jump. Thats how I see it.

I guess if it were me and I felt like I could afford to lose a touch of traction in the corners, I would try the next spring up... if I have too much rotation in the corners and I can't change the spring because of it... I may have more issues than just getting over the jump. Thats how I see it.

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